New conditions for dearomatizing samarium‐ketyl (hetero)arene cyclizations are reported. In many examples of these samarium diiodide‐mediated reactions, lithium bromide and water can be used as additives instead of the carcinogenic and mutagenic hexamethylphosphoramide (HMPA). The best results...
Three efficient methods for five‐membered ring carbocycle synthesis have been developed from simple starting materials using samarium(II) reagents. A Reformatsky aldol reaction proceeded efficiently with samarium(II) iodide using lithium bromide as an additive. A new intramolecular alkylation o...
Allylsamarium bromide adds to oximes derived from aromatic aldehydes and methyl aryl ketones at ambient temperature to afford dihomoallylic secondary amines in moderate to high yields.
In this work, we report the preparation of the Sm 2 O 3 nanoparticle precursors (Sm(OH) 3 ) via a simple W/O microemulsion process, in which microemulsions of cetyltrimethylammonium bromide (CTAB)/alkanol/1-octane/Sm(NO 3 ) 3 aqueous solution were added in...
The complexation of samarium(III) with disodium 2-(2-hydroxy-3-sulfo-5-nitrophenylazo)naphthalene-1,8-dihydroxy-3,6-disulfonate (R) was studied in the presence and absence of cetyltrimethylammonium bromide (CTMABr). Monoligand SmR and mixed-ligand SmR-CTMABr complexes were formed at pH 6 and sho...
Asymmetric dihydroxylations of α,β‐unsaturated ketones in the presence of Sharpless' AD mix‐β™ delivered α,β‐dihydroxy ketones or, if phenylboronic acid was present, the corresponding phenylboronates. The Cα–O bonds of these species were removed at –78 °C – in the former case after ...
The work focuses on the synthesis of Sm2(WO4)3 nanoparticles through a reagent-free aqueous-phase sonochemical reaction between samarium nitrate hexahydrate and Na2WO4.2H2O solutions. The prepared Sm2(WO4)3 nano-structures were also characterized by XRD, EDS and SEM to evaluate their structures ...
A novel samarium-doped cubic phase of copper aluminate nanoparticles (Sm/CuAl2O4) were successfully synthesized by modify sol–gel method with the aid of copper(II) nitrate trihydrate, aluminum nitrate nonahydrate, samarium nitrate hexahydrate, and sucrose without adding external surfactant, cap...
In the current study, samarium tungstate Sm2(WO4)3 nanoparticles were synthesized via a new route based on the reaction between samarium nitrate hexahydrate and sodium tungstate dihydrate in an aqueous solution. Besides, three amino acids such as cysteine, alanine, and glycine were introduce as ...
Samarium(III) nitrate hexahydrate as a catalyst is used as an alternative to conventional acid catalysts in the von Pechmann condensation of phenols with ethyl acetoacetate leading to the formation of coumarin derivatives.
Thermal decomposition of samarium nitrate hexahydrate Sm(NO3)3·6H2O has been investigated by thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and X-ray diffractometry. This is a complex process that involves slow dehydration and fast concomitant internal hydrolysis. I...
A novel class of upconversion luminescent nanocrystals of Yb/Tm:calcium deficient hydroxyapatite were synthesized by co-precipitation method in aqueous solution (pH adjusted to 6) and specially heat-treated with microwave radiation at different temperatures (from 900°C to 1000°C) and times (2–...
.A comprehensive review of the work done by our group, during the last few years, on diode-pumped cw operating bulk Er:Yb phosphate glass is presented. The high performance of this laser in terms of output power, laser slope efficiency, single longitudinal and transverse mode operation, laser tu...
The energy-transfer rate coefficient from ytterbium to erbium (K) and upconversion rate coefficient for erbium (C) are determined by analysis of erbium fluorescence decay under different pumping conditions. A simple rate-equation model was used to describe the fluorescence dynamics. Numerical an...
Arrays of buried channel waveguide lasers and amplifiers were fabricated by silver-sodium ion exchange in erbium-ytterbium doped phosphate glass substrates. The fabrication process, consisting of a thermal diffusion from fused salt followed by a field-assisted burial step, is optimized to get si...
The coordination chemistry of bisphosphonates with Yb 3+ was investigated to evaluate the potential of the UV–vis based detection method using the Yb 3+ –pyrocatechol complexation reaction as a sensor for bisphosphonates. The complexation chemistry of Yb 3+ with phospha...
Absorption spectra and the sites selective fluorescence spectra of Yb 3 + in phosphate glass were investigated at temperatures between 8 and 300 K. Results show that there was an abnormal absorption line in absorption spectra at low temperatures, and the blue shift of the absorption ...
Low-temperature absorption and fluorescence spectra of the Yb 3 + ions were measured in phosphate glass with compositions of (60-65)P 2 O 5 -(4-8)B 2 O 3 -(5-10)Al 2 O 3 -(10-15)K 2 O-(5-10)BaO-(0-2)La 2 O 3 -( 0...
Carbon/carbon (C/C) composites with addition of hafnium carbide (HfC) were prepared by immersing the carbon felt in a hafnium oxychloride aqueous solution, followed by densification and graphitization. Mechanical properties, coefficients of thermal expansion (CTE), and thermal conductivity of th...
Ultrafine hafnium diboride (HfB2) powders were synthesized by the boro/carborthermal reduction process. Fine‐scale mixing of the reactants was achieved by solution‐based processing using hafnium oxychloride (HfOCl2·8H2O) and phenolic resin as the precursor of HfO2 and carbon respectively. The...
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